U.S. patent application number 16/608452 was filed with the patent office on 2020-07-02 for thermochromic pigment compositions.
The applicant listed for this patent is SOCIETE BIC. Invention is credited to Alexander BOURQUE, Guillaume CHOLLET, Anne-Lise DAMIANO, Christelle DEBRAUWER, Francois FOULONNEAU.
Application Number | 20200207699 16/608452 |
Document ID | / |
Family ID | 59521026 |
Filed Date | 2020-07-02 |
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United States Patent
Application |
20200207699 |
Kind Code |
A1 |
DEBRAUWER; Christelle ; et
al. |
July 2, 2020 |
THERMOCHROMIC PIGMENT COMPOSITIONS
Abstract
A thermochromic pigment composition including compounds of
formula (I): ##STR00001## in which: X represents CHR.sub.2, O, OCO
or CH.dbd.CH; Y represents O, COO, or OCOO; R.sub.1 represents H or
(CH.sub.2).sub.pCH.sub.3; R.sub.2 represents phenyl or H; m=12-18;
n=0-14; p=12-18; and on the condition that, if n=0, X represents
CHR.sub.2 or CH.dbd.CH. The thermochromic pigment compositions
having compounds of formula (I), include thermochromic pigment
microcapsules. The thermochromic pigment capsules are useable for
thermochromic pigment compositions in ink which may be used writing
instruments.
Inventors: |
DEBRAUWER; Christelle;
(Saint Germain Sur Morin, FR) ; DAMIANO; Anne-Lise;
(Lagny Sur Marne, FR) ; BOURQUE; Alexander;
(Montevrain, FR) ; FOULONNEAU; Francois;
(Bordeaux, FR) ; CHOLLET; Guillaume; (Leognan,
FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOCIETE BIC |
CLICHY |
|
FR |
|
|
Family ID: |
59521026 |
Appl. No.: |
16/608452 |
Filed: |
April 24, 2018 |
PCT Filed: |
April 24, 2018 |
PCT NO: |
PCT/FR2018/051031 |
371 Date: |
January 6, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07C 43/205 20130101;
C07C 69/44 20130101; C07C 69/736 20130101; C07C 69/616 20130101;
C07C 69/48 20130101; C07C 69/618 20130101; C07C 69/34 20130101;
C09D 11/17 20130101; C09D 11/18 20130101; C09D 11/50 20130101 |
International
Class: |
C07C 69/616 20060101
C07C069/616; C07C 69/34 20060101 C07C069/34; C07C 43/205 20060101
C07C043/205; C09D 11/17 20060101 C09D011/17; C09D 11/50 20060101
C09D011/50; C09D 11/18 20060101 C09D011/18 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 27, 2017 |
FR |
1753677 |
Claims
1. A compound comprising the following formula (I): ##STR00017## in
which: X represents CHR.sub.2, O, or OCO, Y represents O or COO,
R.sub.1 represents H or (CH.sub.2).sub.pCH.sub.3, R.sub.2
represents a phenyl group or H, m=12-18, n=0-14, p=12-18, and on
the condition that, if n=0, X represents CHR.sub.2.
2. (canceled)
3. The compound according to claim 1, corresponding to the
following formula (I.sub.a): ##STR00018## in which: m=12-18, and
n=1-14.
4. The compound according to claim 1, corresponding to the
following formula (I.sub.b): ##STR00019## in which: m=12-18, and
n=0-14.
5. The compound according to claim 1, corresponding to the
following formula (I.sub.c): ##STR00020## in which: X represents
CH.sub.2, or O, Y represents O or COO, m=12-18, and n=1-14.
6. The composition according to claim 1, selected from the group
consisting of the following compounds: ##STR00021##
##STR00022##
7. A thermochromic pigment composition, comprising: (A) at least
one organic electron-donating dye compound, (B) at least one
electron-accepting compound, and at least one compound of formula
(I): ##STR00023## in which: X represents CHR.sub.2, O, OCO, or
CH.dbd.CH, Y represents O or COO, R.sub.1 represents H or
(CH.sub.2).sub.pCH.sub.3, R.sub.2 represents a phenyl group or H,
m=12-18, n=0-14, p=12-18, and on the condition that, if n=0, X
represents CHR.sub.2 or CH.dbd.CH.
8. The thermochromic pigment composition according claim 7, wherein
compound (A) is selected from the group consisting of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (Blue 63, CAS no.: 69898-40-4),
2'-(dibenzylamino)-6'-(diethylamino)fluorane (CAS no.: 34372-72-0),
N,N-dimethyl-4-[2-[2-(octyloxy)phenyl]-6-phenyl-4-pyridinyl]benzenamine
(Yellow CK37, CAS no.: 144190-25-0),
7-(4-diethylamino-2-hexyloxyphenyl)-7-(1-ethyl-2-methyl-1H-indol-3-yl)-7H-
-furo[3,4-b]pyridine-5-one (Blue 203, CAS no.: 98660-18-5),
2-(2,4-dimethylphenylamino)-3-methyl-6-diethylaminofluoran (Black
15, CAS no.: 36431-22-8), and
3,3-bis-(1-butyl-2-methyl-indol-3-yl)-3H-isobenzofuran-1-one (Red
40, CAS no.: 50292-91-6).
9. The thermochromic pigment composition according to claim 7,
wherein compound (B) is selected from the group consisting of
2,2-bis (4-hydroxy-3-methylphenyl)propane (Bisphenol C, CAS no.:
79-97-0), 4-hexyl-1,3-dihydroxybenzene (4-hexylresorcinol, CAS no.:
136-77-6), 4,4'-cyclohexylidenebisphenol (BPZ, CAS no.: 843-55-0),
4,4'-(hexafluoroisopropylidene)diphenol (Bisphenol AF, CAS no.:
1478-61-1), 4,4'-(1-phenylethylidene)bisphenol (CAS no.:
1571-75-1), 2,2'-dihydroxybiphenyl (CAS no.: 1806-29-7),
4,4'-(1,4-phenylenediisopropylidene)bisphenol (CAS no.: 2167-51-3),
1,1-bis(4-hydroxy-3-methyl phenyl)cyclohexane (CAS no.: 2362-14-3),
9,9-bis(4-hydroxyphenyl)fluorene (CAS no.: 3236-71-3),
4,4'-(1,3-phenylenediisopropylidene)bisphenol (CAS no.:
13595-25-0), 1,1,1-tris(4-hydroxyphenypethane (CAS no.:
27955-94-8), 4,4'-(2-ethylhexylidene)diphenol (CAS no.:
74462-02-5),
.alpha.,.alpha.,.alpha.'-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene
(CAS no.: 110726-28-8).
10. A thermochromic pigment microcapsule comprising a composition
according to 7.
11. An ink composition comprising a thermochromic pigment
microcapsules according to claim 10.
12. A writing instrument comprising an ink composition according to
claim 11.
13. The writing instrument according to claim 12, wherein the ink
is erasable and the writing instrument is a ballpoint pen with an
eraser.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a National Stage application of
International Application No. PCT/FR2018/051031, filed on Apr. 24,
2018, now published as WO/2018/197807 and which claims priority to
French Application No. 1753677, filed Apr. 27, 2017, the entire
contents of which is incorporated herein by reference.
FIELD
[0002] The present disclosure relates to novel compounds and to use
thereof as a reaction medium in thermochromic pigment compositions.
The present disclosure also provides thermochromic pigment
microcapsules comprising such thermochromic pigment compositions,
ink compositions comprising such thermochromic pigment
microcapsules, and finally writing instruments comprising such ink
compositions.
DESCRIPTION OF RELATED ART
[0003] Thermochromic pigment compositions have reversible
discoloration properties associated with changes in temperature.
These compositions are employed when an ink marking needs to be
erased repeatedly.
[0004] The thermochromic effect of an ink works through the
combination of the following three compounds: [0005] (A) at least
one organic electron-donor dye or leuco dye compound, [0006] (B) at
least one electron-acceptor or color-developer compound, and [0007]
(C) at least one compound serving as a reaction medium that is
capable of leading to a reversible electron-accepting/donating
reaction attributable to compounds (A) and (B) or thermochromic
regulating agent.
[0008] Temperature changes reversibly bring about the coloration or
discoloration of the inks. Thus, an increase in heat will result in
erasure of the ink, whereas cooling will cause it to appear. These
changes follow the diagram of FIG. 1. In this diagram, the
temperature at which the ink begins to disappear is T3, the
temperature at which the color of the ink has completely
disappeared is T4, and TG is the mean temperature between T3 and
T4. Conversely, the temperature at which the color of the ink
begins to reappear is T2, the temperature at which the color of the
ink has completely reappeared is T1, and TH is the temperature in
the middle between T1 and T2. The range between (TH) and (TG) is
referred to as the color change hysteresis width (.DELTA.H).
SUMMARY
[0009] The present disclosure relates to compounds that enable
thermochromic pigment microcapsules to be prepared that have
optimal melting and crystallization temperature ranges
corresponding respectively to the discoloration and recoloration
temperatures of these compositions. The compounds when used as a
thermochromic regulating agent in thermochromic inks: They exhibit
remarkable hysteresis characteristics and an extremely high color
contrast between the colored state and the discolored state. The
compounds also can be prepared by means of an ecological process,
i.e., from a recycled and biosourced product, 3-pentadecylphenol,
which originates from the waste products of cashew nut
production.
DETAILED DESCRIPTION
[0010] According to a first aspect, the object of the present
disclosure is a compound corresponding to the following formula
(I):
##STR00002##
in which: [0011] X represents CHR.sub.2, O, OCO, or CH.dbd.CH,
[0012] Y represents O or COO, [0013] R.sub.1 represents H or
(CH.sub.2).sub.pCH.sub.3, [0014] R.sub.2 represents a phenyl group
or H, [0015] m=12-18, [0016] n=0-14, [0017] p=12-18, and on the
condition that, if n=0, X represents CHR.sub.2 or CH.dbd.CH.
[0018] In terms of the present disclosure: [0019] if X=OCO: the
oxygen atom is attached to the phenyl group and the carbonyl group
to the (CH.sub.2).sub.n chain, and [0020] if Y=COO: the carbonyl
group is attached to the (CH.sub.2).sub.n chain and the oxygen atom
to the phenyl group.
[0021] In formula (I) above, X is selected from among CHR.sub.2, O,
or OCO.
[0022] In formula (I) above, m can be selected independently from
among the following integers: 12, 13, 14, 15, 16, 17, or 18.
[0023] In formula (I) above, n can be selected independently from
among the following integers: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
12, 13, or 14.
[0024] In formula (I) above, p can be selected independently from
among the following integers: 12, 13, 14, 15, 16, 17, or 18.
[0025] In formula (I) above, n=0-10.
[0026] In formula (I) above, p=14.
[0027] The compound of formula (I) is a compound in which: [0028] X
represents CHR.sub.2, O, or OCO, [0029] Y represents O or COO,
[0030] R.sub.1 represents H or (CH.sub.2).sub.pCH.sub.3, [0031]
R.sub.2 represents a phenyl group or H, [0032] m=12-18, and [0033]
n=0-14, or n=0-10, [0034] p=12-18, or p=14, on the condition that,
if n=0, X represents CHR.sub.2.
[0035] According to a first embodiment, the compound corresponds to
the following formula (I.sub.a):
##STR00003##
in which: [0036] m=12-18, and [0037] n=1-14, or n=1-10,
[0038] in formula (I.sub.a): m=14.
[0039] in formula (I.sub.a): n=8.
[0040] According to a second embodiment, the compound corresponds
to the following formula (I.sub.b):
##STR00004##
in which: [0041] m=12-18, and [0042] n=0-14, or n=0-10.
[0043] in formula (I.sub.b): m=14.
[0044] in formula (I.sub.b): n=1.
[0045] According to a third embodiment, the compound corresponds to
the following formula (I.sub.c):
##STR00005##
in which: [0046] X represents CH.sub.2, O, or CH.dbd.CH, [0047] Y
represents O or COO, [0048] m=12-18, and [0049] n=1-14, or n=1-10,
or n=1-8.
[0050] in formula (I.sub.c): m=14.
[0051] in formula (I.sub.c): n=2.
[0052] The compounds of formula (I.sub.a), (I.sub.b), and (I.sub.c)
can be synthesized according to the first two synthetic routes
described below. The compound of formula (I.sub.c) can also be
synthesized according to the third synthetic route described
below.
[0053] The first synthetic route corresponds to the following
reaction scheme:
##STR00006##
[0054] In this first synthetic route, alcohol acts as a solvent. It
is used in excess, or at an alcohol/carboxylic acid ratio of 1.5/1
to 3/1, or of 2/1. The mixture of alcohol and carboxylic acid is
heated to a temperature ranging from 120 to 200.degree. C., or from
140 to 160.degree. C., under reduced pressure, or between 200 and
800 mbar, until the acid is completely consumed. The mixture is
heated under reduced pressure for a period ranging from 1 to 4
days. The compound of formula (I.sub.a), (I.sub.b), or (I.sub.c)
obtained is then purified by recrystallization.
[0055] The second synthetic route corresponds to the following
reaction scheme:
##STR00007##
[0056] In this second synthetic route, the phenol is solubilized
with a catalyst in an aprotic polar solvent such as tetrahydrofuran
(THF). The catalyst is a volatile base such as triethylamine. The
mixture is kept cold at a temperature ranging from -20 to
30.degree. C., or from 0 to 20.degree. C. The mixture is kept cold
in an ice bath or in a solid CO.sub.2 bath immersed in a solvent
such as acetone or ethanol. The mixture is rendered inert by adding
nitrogen. The acid chloride is then slowly added dropwise over a
period of 15 to 60 minutes. The phenol/acid chloride ratio used is
1.1/1 to 1/1.1, or 1/1. The temperature of the mixture is then
raised to room temperature (25.degree. C.), and the mixture is
maintained at this temperature for 1 to 3 hours, preferably 2
hours, under stirring. The compound of formula (I.sub.a),
(I.sub.b), or (I.sub.c) obtained is then purified by
recrystallization.
[0057] The compound of formula (I.sub.c) can also be synthesized
according to the following synthetic route:
##STR00008##
where the substituent X' represents a halogen atom selected from
among Cl, Br, I, or F, and preferably the Br atom.
[0058] In this synthetic route, the compounds of formula (I.sub.c)
can be prepared: [0059] Either by solubilization of the reagents in
a polar solvent such as tert-butanol in the presence of a strong
base such as sodium hydroxide. The alcohol/halogenated compound
ratio used is 1/1 to 1.4/1, or 1.2/1. The reagent mixture is heated
under reflux at 75 to 90.degree. C. for 2 to 10 hours, preferably 6
hours. The compound of formula (I.sub.c) obtained is then purified
by recrystallization [0060] Or by solubilization of the reagents in
a polar solvent such as acetonitrile in the presence of a strong
base such as potassium carbonate. The alcohol/halogenated compound
ratio used is 1/1 to 1.4/1, or 1.2/1. The reagent mixture is heated
under reflux at a temperature of 75 to 90.degree. C. for 5 to 10
days, preferably 7 days. The mixture is then filtered in order to
remove the weak base. The compound of formula (I.sub.c) obtained is
then purified by recrystallization.
[0061] The compound of formula (I) is chosen from among the
following compounds:
##STR00009## ##STR00010##
[0062] The melting temperature of the compound of formula (I) can
vary from 20 to 80.degree. C., or from 30 to 80.degree. C., or from
40 to 70.degree. C. It is this optimum melting temperature that
makes the compound of formula (I) an ideal compound that has the
properties required for use as a thermochromic regulating agent in
thermochromic pigment compositions.
[0063] Therefore, another object of the disclosure is a
thermochromic pigment composition comprising:
(A) at least one organic electron-donor dye or leuco dye compound,
(B) at least one electron-acceptor or color-developer compound, and
(C) at least one compound of formula (I) as defined according to
the disclosure.
[0064] The weight ratios of compounds (A), (B), and (C) are
influenced by the nature and concentration of each of these
compounds.
[0065] The weight ratio of organic electron-donating dye compound
(A) can vary from 1 to 10%, or from 1 to 6%, or from 2 to 4%, by
weight relative to the total weight of the thermochromic pigment
composition.
[0066] The weight ratio of electron-accepting compound (B) can vary
from 1 to 20%, or from 1 to 14%, or from 4 to 10%, by weight
relative to the total weight of the thermochromic pigment
composition.
[0067] The weight ratio of compound (C) of formula (I) acting as a
reaction medium can vary from 70 to 98%, or from 80 to 98%, or from
86 to 94%, by weight relative to the total weight of the
thermochromic pigment composition.
[0068] Therefore, the thermochromic pigment composition may
comprise:
(A) from 1 to 10%, or from 1 to 6%, or from 2 to 4%, by weight of
at least one organic electron-donating dye compound, (B) from 1 to
20%, or from 1 to 14%, or from 4 to 10%, by weight of at least one
electron-accepting compound, and (C) from 70 to 98%, or from 80 to
98%, or from 86 to 94%, by weight of at least one compound of
formula (I).
[0069] The thermochromic pigment composition comprises:
(A) from 2 to 4% by weight of at least one organic
electron-donating dye compound, (B) from 4 to 10% by weight of at
least one electron-accepting compound, and (C) from 86 to 94% by
weight of at least one compound of formula (I).
[0070] The thermochromic pigment composition has a color change
hysteresis width (.DELTA.H) after encapsulation ranging from 20 to
80.degree. C., or from 30 to 80.degree. C., or from 40 to
70.degree. C.
[0071] Some noteworthy organic electron-donating dye compounds (A)
include conventionally known compounds such as diphenylmethane
phthalides, phenylindolyl phthalides, indolyl phthalides,
diphenylmethane azaphthalides, phenylindolyl azaphthalides,
fluoranes, styrylquinolines, and diazarhodamine lactones, with
examples of these compounds being presented hereinafter.
[0072] The organic electron-donating dye compound (A) can thus be
chosen from
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-a-
zaphthalide (Blue 63, CAS no.: 69898-40-4),
3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalate (CAS no.:
1552-42-7), 2'-chloro-6'-(diethylamino)-3'-methylfluorane (CAS no.:
21121-62-0), 6'-(diethylamino)-1',3'-dimethylfluorane (CAS no.:
21934-68-9), 2-chloro-6-(diethylamino)-fluorane (CAS no.:
26567-23-7), 3-diethylaminobenzofluorane (CAS no.: 26628-47-7),
3',6'-bis(diethylamino)-2-(4-nitrophenyl)spiro
[isoindole-1,9'-xanthene]-3-one (CAS no.: 29199-09-5),
2-phenylamino-3-methyl-6-diethylaminofluorane (CAS no.:
29512-49-0), 2'-(dibenzylamino)-6'-(diethylamino)fluorane (CAS no.:
34372-72-0),
2-(2,4-dimethylphenylamino)-3-methyl-6-diethylaminofluorane (CAS
no.: 36431-22-8),
3-(1,2-dimethyl-3-indolyl)-3-[4-(diethylamino)-2-methylphenyl]phthalide
(CAS no.: 36499-49-7), 3',6'-dimethoxyfluorane (CAS no.:
36886-76-7),
3,3-bis-(1-butyl-2-methyl-indol-3-yl)-3H-isobenzofuran-1-one (Red
40, CAS no.: 50292-91-6),
3,3-bis-(2-methyl-1-octyl-1H-indol-3-yl)-3H-isobenzofuran-1-one
(CAS no.: 50292-95-0),
2'-anilino-6'-[ethyl(p-tolyl)amino]-3'-methylspiro[isobenzofuran-1(3H),9'-
-[9H]xanthene]-3-one (CAS no.: 59129-79-2),
3-(N-ethyl-n-isopentylamino)-6-methyl-7-anilino fluorene (CAS no.:
70516-41-5),
3-[4-(diethylamino)phenyl]-3-(1-ethyl-2-methyl-1H-indol-3-yl)phthalide
(CAS no.: 75805-17-3),
2'-(2-chloroanilino)-6'-(dibutylamino)fluorane (CAS no.:
82137-81-3), 2-phenylamino-3-methyl-6-dibutylaminofluorane (CAS
no.: 89331-94-2),
3-(1-butyl-2-methyl-1H-indol-3-yl)-6-(dimethylamino)-3-[4-(dimethylamino)-
phenyl]-3-(1(3H)-isobenzofuranone (CAS no.: 92453-31-1),
7-(4-diethylamino-2-hexyloxyphenyl)-7-(1-ethyl-2-methyl-1H-indol-3-yl)-7H-
-furo[3,4-b]pyridine-5-one (Blue 203, CAS no.: 98660-18-5),
7,7-bis[4-(diethylamino)-2-ethoxyphenyl]furo[3,4-b]pyridine-5-one
(CAS no.: 132467-74-4),
N,N-dimethyl-4-[2-[2-(octyloxy)phenyl]-6-phenyl-4-pyridinyl]benzenamine
(Yellow CK37, CAS no.: 144190-25-0),
3-(2,2-bis(1-ethyl-2-methylindol-3-yl)vinyl)-3-(4-diethylaminophenyl)-pht-
halide (CAS no.: 148716-90-9).
[0073] Preferably, the organic electron-donating dye compound (A)
is selected from among
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (Blue 63, CAS no.: 69898-40-4),
2'-(dibenzylamino)-6'-(diethylamino)fluorane (CAS no.: 34372-72-0),
N,N-dimethyl-4-[2-[2-(octyloxy)phenyl]-6-phenyl-4-pyridinyl]benzenamine
(Yellow CK37, CAS no.: 144190-25-0),
7-(4-diethylamino-2-hexyloxyphenyl)-7-(1-ethyl-2-methyl-1H-indol-3-yl)-7H-
-furo[3,4-b]pyridine-5-one (Blue 203, CAS no.: 98660-18-5),
2-(2,4-dimethylphenylamino)-3-methyl-6-diethylaminofluoran (Black
15, CAS no.: 36431-22-8), and
3,3-bis-(1-butyl-2-methyl-indol-3-yl)-3H-isobenzofuran-1-one (Red
40, CAS no.: 50292-91-6).
[0074] Some noteworthy electron-accepting compounds (B) include but
are not limited to compounds having an active proton, such as
compounds having a phenolic hydroxyl group (monophenols or
polyphenols), and derivatives thereof having substituents such as
alkyl group, an aryl group, an acyl group, an alkoxycarbonyl group,
a carboxy group, esters thereof, an amido group or a halogen atom,
and phenol-aldehyde condensed resins such as bisphenols or
trisphenols.
[0075] In terms of the present disclosure: [0076] "Alkyl" refers to
a saturated, linear or branched, hydrocarbon aliphatic group in
C.sub.1-C.sub.20, in C.sub.1-C.sub.12, in C.sub.1-C.sub.6, or in
C.sub.1-C.sub.4. The term "branched" means that at least one lower
alkyl group such as methyl or ethyl is carried by a linear alkyl
chain. Some noteworthy alkyl groups include methyl, ethyl,
n-propyl, i-propyl, n-butyl, t-butyl, and n-pentyl groups. [0077]
"Aryl" refers to any functional group or substituent derived from
at least one aromatic ring; an aromatic cycle corresponds to any
mono- or polycyclic group plane containing a delocalized .pi.
system in which each atom of the cycle has an orbital p, said
orbitals p overlapping one another; noteworthy aryl groups of this
kind include phenyl, biphenyl, naphthalene, and anthracene groups.
The aryl groups comprise from 4 to 12 carbon atoms, or from 5 to 6
carbon atoms. The aryl group is a phenyl group.
[0078] Therefore, the electron-accepting compound (B) can be
selected from among 2,2-bis(4-hydroxy-3-methylphenyl)propane
(Bisphenol C, CAS no.: 79-97-0), 4-hexyl-1,3-dihydroxybenzene
(4-hexylresorcinol, CAS no.: 136-77-6),
4,4'-cyclohexylidenebisphenol (BPZ, CAS no.: 843-55-0),
4,4'-(hexafluoroisopropylidene)diphenol (Bisphenol AF, CAS no.:
1478-61-1), 4,4'-(1-phenylethylidene)bisphenol (CAS no.:
1571-75-1), 2,2'-dihydroxybiphenyl (CAS no.: 1806-29-7),
4,4'-ethylidenebisphenol (CAS no.: 2081-08-5),
4,4'-(1,4-phenylenediisopropylidene)bisphenol (CAS no.: 2167-51-3),
1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (CAS no.: 2362-14-3),
9,9-bis(4-hydroxyphenyl)fluorene (CAS no.: 3236-71-3),
4,4'-(1,3-phenylenediisopropylidene)bisphenol (CAS no.:
13595-25-0), 1,1,1-tris(4-hydroxyphenyl)ethane (CAS no.:
27955-94-8), 4,4'-(2-ethylhexylidene)diphenol (CAS no.:
74462-02-5),
.alpha.,.alpha.,.alpha.'-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene
(CAS no.: 110726-28-8), 4-(1,1,3,3-tetramethylbutyl)phenol (CAS
no.: 140-66-9), 4-hydroxydiphenylether (CAS no.: 831-82-3),
bis(2-hydroxy-1-naphthyl)methane (CAS no.: 1096-84-0),
4-(methylsulfonyl)phenol (CAS no.: 14763-60-1),
4-hydroxyphenyl-4'-isopropoxyphenyl sulfone (CAS no.: 95235-30-6),
4,4'-dihydroxybiphenyl (CAS no.: 92-88-6), 4-hydroxybiphenyl (CAS
no.: 92-69-3), p-hydroxycumene (CAS no.: 99-89-8),
2,4-dihydroxybenzophenone (CAS no.: 131-56-6), l'hydroquinone
monomethylether (MEHQ, CAS no.: 150-76-5), 3-n-pentadecylphenol
(CAS no.: 501-24-6), 4-(2-phenylisopropyl)phenol (CAS no.:
599-64-4), 5-chloro-2-(2,4-dichlorophenoxy)phenol (CAS no.:
3380-34-5),
N-(p-toluenesulfonyl)-N'-(3-(p-toluenesulfonyloxy)phenyl)urea (CAS
no.: 232938-43-1), 2,2-bis(3,5-dibromo-4-hydroxyphenyppropane (CAS
no.: 79-94-7), 4,4'-isopropylidenediphenol (CAS no.: 80-05-7), and
4,4'-sulfonyldiphenol, (BPS, CAS no.: 80-09-1).
[0079] Preferably, the electron-accepting compound (B) is selected
from among 2,2-bis(4-hydroxy-3-methylphenyl)propane (Bisphenol C,
CAS no.: 79-97-0), 4-hexyl-1,3-dihydroxybenzene (4-hexylresorcinol,
CAS no.: 136-77-6), 4,4'-cyclohexylidenebisphenol (BPZ, CAS no.:
843-55-0), 4,4'-(hexafluoroisopropylidene)diphenol (Bisphenol AF,
CAS no.: 1478-61-1), 4,4'-(1-phenylethylidene)bisphenol (CAS no.:
1571-75-1), 2,2'-dihydroxybiphenyl (CAS no.: 1806-29-7),
4,4'-(1,4-phenylenediisopropylidene)bisphenol (CAS no.: 2167-51-3),
1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (CAS no.: 2362-14-3),
9,9-bis(4-hydroxyphenyl)fluorene (CAS no.: 3236-71-3),
4,4'-(1,3-phenylenediisopropylidene)bisphenol (CAS no.:
13595-25-0), 1,1,1-tris(4- hydroxyphenyl)ethane (CAS no.:
27955-94-8), 4,4'-(2-ethylhexylidene)diphenol (CAS no.:
74462-02-5), and
.alpha.,.alpha.,.alpha.'-tris(4-hydroxyphenyl)-1-ethyl-4-isopropyl
benzene (CAS no.: 110726-28-8).
[0080] The thermochromic pigment composition is prepared by
dissolving compounds (A) and (B) in compound (C) of formula (I),
followed by stirring until a homogeneous mixture is obtained using
an agitator such as a homo-mixer or disperser.
[0081] Compounds (A) and (B) combined in this manner with the
compound of formula (I) can be formulated as microcapsules. The
thermochromic pigment composition encapsulated in microcapsules to
form thermochromic pigment microcapsules. Such thermochromic
pigment microcapsules constitute another object of the disclosure.
They have characteristics in as much as they are resistant to
mechanical stresses, insoluble and therefore dispersible in water,
and slow to agglomerate.
[0082] The melting temperature (or discoloration temperature T4) of
the thermochromic pigment microcapsules of the disclosure can vary
from 20 to 80.degree. C., or from 30 to 80.degree. C., or from 40
to 70.degree. C.
[0083] The crystallization temperature (or recoloration temperature
T1) of the thermochromic pigment microcapsules can vary from -40 to
20.degree. C., or from -30 to 10.degree. C., or from -20 to
0.degree. C.
[0084] The thermochromic pigment microcapsules have a mean diameter
that can range from 0.5 to 30 .mu.m, or from 1 to 10 .mu.m, or from
3-5 .mu.m. This mean diameter corresponds to d90 by volume and
means that 90% by volume of the microcapsules consists of
microcapsules having a size within the indicated range. This mean
diameter can be determined by laser granulometry using a Zetasizer
Nano ZS device from Malvern Instruments.
[0085] The microencapsulation methods used include but are not
limited to conventional methods, such as: [0086] chemical processes
that are based on the in situ formation of the encapsulating
microcapsules, for example through interfacial polymerization or
polycondensation, these processes being preferred, [0087]
physicochemical processes, for example through phase separation or
coacervation, solvent evaporation-extraction, thermal gelation of
emulsions (hot melt), or [0088] mechanical processes, for example
through nebulization/drying (spray-drying), gelling or freezing
drops, or through coating on a fluidized bed (spray-coating).
[0089] The thermochromic pigment microcapsules are based on
aminoplast resin, on melamine resin, urea resin, or benzoguanamine
resin.
[0090] The thermochromic pigment microcapsules prepared from
melamine resin by means of in situ polymerization.
[0091] Another object of the disclosure is an ink composition
comprising thermochromic pigment microcapsules.
[0092] The thermochromic pigment microcapsules that are present in
the ink composition represent from 5 to 50% by weight of the total
weight of the ink composition.
[0093] Otherwise, the ink composition is composed primarily of
water. The water represents 40 to 80% by weight of the total weight
of the ink composition.
[0094] The ink composition can also contain one or more
water-miscible cosolvents. For instance, the ink composition can
contain an organic or aqueous solvent, or an aqueous solvent.
[0095] Some noteworthy solvents that can be added to the ink
composition include water and water-miscible polar solvents, for
example: [0096] alcohols: linear or branched C.sub.1-C.sub.15
alcohols such as isopropanol, butanol, isobutanol, pentanol, or
benzyl alcohol; glycerin; diglycerin; polyglycerin [0097] esters
such as ethyl acetate or propyl acetate, [0098] carbonate esters
such as propylene carbonate or ethylene carbonate, [0099] ketones,
such as methyl isobutyl ketone (MIBC), acetone, or cyclohexanone,
[0100] glycols, such as ethylene glycol, diethylene glycol,
triethylene glycol, propylene glycol, polyethylene glycol, ethylene
glycol monomethyl ether, 3-butylene glycol, and thiodiethylene
glycol, [0101] amides, such as dimethylacetamide or
dimethylformamide, and [0102] mixtures thereof.
[0103] The solvent or solvents make up 5 to 20% by weight of the
total weight of the ink composition.
[0104] The ink composition can also contain one or more specific
adjuvants which may play different roles depending on the intended
end use. These applications may include ink for screen printing,
offset printing, gravure printing, powder coating, electrostatic
coating, electroplating, roll coating, and inkjet printing, as well
as inks for writing instruments such as ballpoint pens, brush pens,
markers, and colored pencils. The ink composition can also be added
to a thermoplastic or thermosetting resin composition for forming
molded parts.
[0105] Some noteworthy adjuvants among those mentioned above
include: [0106] rheology modifiers (shear-thinning agents) that are
capable of producing a gelling effect, such as xanthan gum or gum
arabic, [0107] defoamers, such as modified aqueous dispersions of
polysiloxane (MOUSSEX.RTM. from Synthron) [0108] pH regulators,
such as sodium hydroxide, triethanolamine, [0109] surfactants, such
as polyether polyols (TERGITOL.TM. from DOW), [0110] biocides, such
as isothiazolinones (ACTICIDE.RTM. from Thor) [0111] anticorrosive
agents, such as benzotriazole, [0112] lubricants, [0113]
dispersants, [0114] coalescing agents, [0115] crosslinking agents,
[0116] wetting agents, [0117] plasticizers, [0118] antioxidants,
[0119] UV stabilizers.
[0120] The disclosure further relates to writing instruments
comprising an ink composition according to the disclosure. These
instruments generally consist of a body containing the ink
composition, and possibly a friction element. The writing
instrument according is selected from among ballpoint pens,
pencils, chalks, and ballpoint pens with friction-erasable ink. The
friction element of the writing instrument is preferably a rubber
eraser.
[0121] The substrates to which the ink composition can be applied
are paper, fibers, leather, plastic, glass, metal, wood, and
concrete.
[0122] In addition to the foregoing, the disclosure also comprises
other provisions which will become evident from the description
that follows, which relates to the synthesis of compounds of
formula (I), characterization thereof, and use thereof as a
thermochromic regulating agent in thermochromic pigment
compositions.
EXAMPLES
Example 1
[0123] Compounds (6), (7), (8), (9), (10), and (11) of the
following formulas:
##STR00011##
are prepared: [0124] Either by solubilization of the reagents in
acetonitrile in the presence of potassium carbonate under reflux
(85.degree. C.) for 7 days according to the following synthesis
scheme:
##STR00012##
[0125] The potassium carbonate is then removed by filtration.
[0126] Or by solubilization of the reagents in tert-butanol in the
presence of sodium hydroxide under reflux (85.degree. C.) for 6
hours according to the following synthesis scheme:
##STR00013##
[0127] Compounds (6), (7), (8), (9), (10), and (11) synthesized in
this manner are purified by successive recrystallizations.
[0128] Synthesis of Compound (6):
[0129] 20 g of 3-pentadecylphenol (CAS no. 501-24-6), 16 g of
1-bromo-3-phenylpropane (CAS no. 637-59-2), and 11 g of calcium
carbonate K.sub.2CO.sub.3 (CAS no. 584-08-7) are mixed in 100 ml of
acetonitrile and then heated under reflux at 85.degree. C. for 7
days.
[0130] The potassium carbonate, K.sub.2CO.sub.3, is removed by
filtration. The acetonitrile is then evaporated, and the solid
obtained is recrystallized in 150 ml of ethanol (purity: 95%). The
reaction medium is heated under reflux until solubilization is
complete, then cooled to room temperature until the product has
precipitated. The solid obtained is washed three times with 50 ml
of ethanol (purity: 95%).
[0131] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 96% pure.
[0132] Synthesis of Compound (7):
[0133] 19.7 g of 3-pentadecylphenol (CAS no. 501-24-6) are
solubilized in 20 ml of tert-butanol and then heated to 40.degree.
C. in order to produce a homogeneous mixture. 3.4 g of sodium
hydroxide (CAS no. 1310-73-2) are diluted in 10 ml of distilled
water and then added to the reaction medium. After 15 minutes of
stirring, 10 g of (2-bromoethyl) benzene (CAS no. 103-63-9) are
added to the mixture, and the reaction medium is heated at
80.degree. C. for 6 hours.
[0134] The solid product is recovered by recrystallization and
filtration and then purified by three successive recrystallizations
in 200 ml of ethanol.
[0135] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 96% pure.
[0136] Synthesis of Compound (8):
[0137] 20 g of 3-pentadecylphenol (CAS no. 501-24-6), 16 g of
.beta.-bromophenetole (CAS no. 637-59-2), and 11 g of calcium
carbonate K.sub.2CO.sub.3 (CAS no. 584-08-7) are mixed in 100 ml of
acetonitrile and then heated under reflux at 85.degree. C. for 7
days.
[0138] The potassium carbonate, K.sub.2CO.sub.3, is removed by
filtration. The acetonitrile is then evaporated, and the solid
obtained is recrystallized in 150 ml of ethanol (purity: 95%). The
reaction medium is heated under reflux until solubilization is
complete, then cooled to room temperature until the product has
precipitated. The solid obtained is washed three times with 50 ml
of ethanol (purity: 95%).
[0139] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 99% pure.
[0140] Synthesis of Compound (9):
[0141] 17 g of 3-pentadecylphenol (CAS no. 501-24-6) are
solubilized in 100 ml of tert-butanol and then heated to 40.degree.
C. in order to produce a homogeneous mixture. 2.9 g of sodium
hydroxide (CAS no. 1310-73-2) are diluted in 10 ml of distilled
water and then added to the reaction medium. After 15 minutes of
stirring, 10 g of 3-phenoxypropyl (CAS no. 588-63-6) are added to
the mixture, and the reaction medium is heated at 80.degree. C. for
6 hours.
[0142] The solid product is recovered by recrystallization and
filtration and then purified by three successive recrystallizations
in 150 ml of ethanol.
[0143] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 99% pure.
[0144] Synthesis of Compound (10):
[0145] 15.8 g of 3-pentadecylphenol (CAS no. 501-24-6) are
solubilized in 100 ml of tert-butanol and then heated to 40.degree.
C. in order to produce a homogeneous mixture. 2.8 g of sodium
hydroxide (CAS no. 1310-73-2) are diluted in 10 ml of distilled
water and then added to the reaction medium. After 15 minutes of
stirring, 10 g of 4-bromobutyl phenyl ether (CAS no. 1200-03-9) are
added to the mixture, and the reaction medium is heated at
80.degree. C. for 6 hours.
[0146] The solid product is recovered by recrystallization and
filtration and then purified by three successive recrystallizations
in 150 ml of ethanol.
[0147] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 98% pure.
[0148] Synthesis of Compound (11):
[0149] 14 g of 3-pentadecylphenol (CAS no. 501-24-6) are
solubilized in 20 ml of tert-butanol and then heated to 40.degree.
C. in order to produce a homogeneous mixture. 2.5 g of sodium
hydroxide (CAS no. 1310-73-2) are diluted in 10 ml of distilled
water and then added to the reaction medium. After 15 minutes of
stirring, 10 g of 6-phenoxypropyl (CAS no. 57795-97-2) are added to
the mixture, and the reaction medium is heated at 80.degree. C. for
8 hours.
[0150] The solid product is recovered by recrystallization and
filtration and then purified by three successive recrystallizations
in 150 ml of ethanol.
[0151] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 96% pure.
[0152] The melting temperatures T.sub.FUS of compounds (6), (7),
(8), (9), (10), and (11) obtained were measured by means of
differential scanning calorimetry (DSC) using a TA Instruments Q20
apparatus over a temperature range of -50 to 100.degree. C. at
heating/cooling rates of +/-20.degree. C./minute. The temperatures
measured are shown in table 1 below.
TABLE-US-00001 TABLE 1 Compound of formula (I) T.sub.FUS
(.degree.C.) Compound (6) 35 Compound (7) 44 Compound (8) 71
Compound (9) 56 Compound (10) 59 Compound (11) 54
Example 2
[0153] Compounds (1), (2), (3), (4), (5), (12), (13), (14), (15),
and (16) of the following formulas:
##STR00014##
are prepared: [0154] Either from a carboxylic acid using an alcohol
having a melting point below 60.degree. C. as the solvent and
paratoluenesulfonic acid as a reaction catalyst. The mixture is
heated to a temperature between 120 and 150.degree. C. under a
slight vacuum in order to allow for the removal of water and thus a
shifting of equilibrium to the synthesis of compounds of formula
(I).
##STR00015##
[0155] The compounds of formula (I) obtained are purified by
recrystallization with a single alcohol. [0156] Either from an
alcohol by solubilizing it in tetrahydrofuran (THF) with
triethylamine as catalyst at a temperature between 0 and 20.degree.
C. The acid chloride is then slowly added dropwise over 30 minutes.
The mixture is then reheated to room temperature (25.degree. C.)
for 2 hours under stirring.
##STR00016##
[0157] The compounds (1), (2), (3), (4), (5), (12), (13), (14),
(15), and (16) obtained are purified by recrystallization.
[0158] Synthesis of Compound (1):
[0159] 17.8 g of 3-pentadecylphenol (CAS no. 501-24-6) and 5.8 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and then rendered inert by adding
nitrogen. 10 g of phenoxyacetate chloride (CAS no. 701-99-5) are
added dropwise for 15 minutes. Once the addition is completed, the
reaction medium is stirred for 30 minutes at room temperature.
[0160] The reaction medium is then extracted with 100 ml of ethyl
acetate. The organic phase is recovered and washed three times with
100 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0161] The product is recrystallized twice using isopropanol.
[0162] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 95% pure.
[0163] Synthesis of Compound (2):
[0164] 18 g of 3-pentadecylphenol (CAS no. 501-24-6) and 6.5 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and then rendered inert by adding
nitrogen. 10 g of trans-3-phenylacryloyl chloride (CAS no.
102-92-1) diluted in 10 ml of tetrahydrofuran are added dropwise
for 15 minutes. Once the addition is completed, the reaction medium
is stirred for 30 minutes at room temperature.
[0165] The reaction medium is then extracted with 150 ml of ethyl
acetate. The organic phase is recovered and washed three times with
150 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0166] The product is recrystallized twice using ethanol.
[0167] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 90% pure.
[0168] Synthesis of Compound (3):
[0169] 20 g of 3-pentadecylphenol (CAS no. 501-24-6), 19.7 g of
3-phenylpropionic acid (CAS no. 501-52-0), and 200 mg of
p-toluenesulfonic acid monohydrate (APTS) (CAS no. 6192-52-5) are
mixed and heated at 140.degree. C. for 3 days under reduced
pressure (400 mbar).
[0170] The reaction medium is purified by adding 50 ml of ethanol
(purity: 95%) and then heating under reflux until solubilization is
complete. The reaction medium is then cooled to room temperature
until the product has precipitated. The solid obtained is washed
three times with 30 ml of ethanol (purity: 95%).
[0171] The product is recrystallized twice using isopropanol.
[0172] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 83% pure.
[0173] Synthesis of Compound (4):
[0174] 20 g of 3-pentadecylphenol (CAS no. 501-24-6), 30 g of
3,3-diphenylpropionic acid (CAS no. 606-83-7), and 200 mg of
p-toluenesulfonic acid monohydrate (APTS) (CAS no. 6192-52-5) are
mixed and heated at 160.degree. C. for 3 days under reduced
pressure (600 mbar).
[0175] The reaction medium is purified by adding 150 ml of ethanol
(purity: 95%), then heated to reflux until solubilization is
complete. The reaction medium is then cooled to room temperature
until the product has precipitated. The solid obtained is washed
three times with 30 ml of ethanol (purity: 95%).
[0176] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 95% pure.
[0177] Synthesis of Compound (5):
[0178] 13.8 g of 3-pentadecylphenol (CAS no. 501-24-6) and 5.0 g of
triethylamine (CAS no. 121-44-8) are solubilized in 150 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and rendered inert by adding
nitrogen. 10.4 g of diphenylacetyl chloride (CAS no. 1871-76-7)
diluted in 15 ml of tetrahydrofuran are added dropwise for 15
minutes. Once the addition is completed, the reaction medium is
stirred for 30 minutes at room temperature.
[0179] The reaction medium is then extracted with 100 ml of ethyl
acetate. The organic phase is recovered and washed three times with
150 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0180] The product is recrystallized twice using ethanol cooled to
-20.degree. C.
[0181] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 86% pure.
[0182] Synthesis of Compound (12):
[0183] 38.9 g of 3-pentadecylphenol (CAS no. 501-24-6) and 6.8 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and rendered inert by adding
nitrogen. 10 g of succinic acid chloride (CAS no. 543-20-4) are
added dropwise for 15 minutes. Once the addition is completed, the
reaction medium is stirred for 30 minutes at room temperature.
[0184] The product obtained is extracted with 100 ml of ethyl
acetate. The organic phase is recovered and washed three times with
150 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0185] The product is recrystallized twice using isopropanol.
[0186] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 94% pure.
[0187] Synthesis of Compound (13):
[0188] 33.1 g of 3-pentadecylphenol (CAS no. 501-24-6) and 8.1 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and rendered inert by adding
nitrogen. 10 g of adipic acid chloride (CAS no. 111-50-2) are added
dropwise for 15 minutes. Once the addition is completed, the
reaction medium is stirred for 30 minutes at room temperature.
[0189] The product obtained is extracted with 100 ml of ethyl
acetate. The organic phase is recovered and washed three times with
150 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0190] The product is recrystallized twice using isopropanol.
[0191] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 87% pure.
[0192] Synthesis of Compound (14):
[0193] 15.9 g of 3-pentadecylphenol (CAS no. 501-24-6) and 5.8 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and rendered inert by adding
nitrogen. 10 g of suberic acid chloride (CAS no. 10027-07-3) are
added dropwise for 15 minutes. Once the addition is completed, the
reaction medium is stirred for 30 minutes at room temperature.
[0194] The product obtained is extracted with 100 ml of ethyl
acetate. The organic phase is recovered and washed three times with
150 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0195] The product is recrystallized twice using isopropanol.
[0196] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 96% pure.
[0197] Synthesis of Compound (15):
[0198] 20 g of 3-pentadecylphenol (CAS no. 501-24-6) and 7.2 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is cooled
to 5.degree. C. and maintained at this temperature in an ice bath.
The reaction medium is rendered inert by adding nitrogen. 7.9 g of
sebacoyl chloride (CAS no. 111-19-3) are added dropwise for 15
minutes. The reaction medium is then stirred for 2 hours at room
temperature.
[0199] The product obtained is extracted with 200 ml of ethyl
acetate. The organic phase is recovered and washed three times with
100 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0200] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 90% pure.
[0201] Synthesis of Compound (16):
[0202] 22.7 g of 3-pentadecylphenol (CAS no. 501-24-6) and 8.3 g of
triethylamine (CAS no. 121-44-8) are solubilized in 250 ml of
tetrahydrofuran (CAS no. 109-99-9). The reaction medium is
maintained at room temperature and rendered inert by adding
nitrogen. 10 g of lauric acid chloride (CAS no. 4834-98-4) are
added dropwise for 15 minutes. Once the addition is completed, the
reaction medium is stirred for 30 minutes at room temperature.
[0203] The product obtained is extracted with 100 ml of ethyl
acetate. The organic phase is recovered and washed three times with
150 ml of water. The organic phase is then dried over sodium
sulfate and the solvent evaporated.
[0204] The product is recrystallized twice using isopropanol.
[0205] Gas chromatographic (GPC) analysis of the product obtained
using a PerkinElmer Clarus.RTM. 680/600S revealed that the product
was 94% pure.
[0206] The melting temperatures of compounds (1), (2), (3), (4),
(5), (12), (13), (14), (15), and (16) obtained were measured by
means of differential scanning calorimetry (DSC) using a TA
Instruments Q20 apparatus over a temperature range of -50 to
100.degree. C. at heating/cooling rates of +/-20.degree. C./minute.
The temperatures measured are shown in table 2 below.
TABLE-US-00002 TABLE 2 Compound of formula (I) T.sub.FUS
(.degree.C.) Compound (1) 41 Compound (2) 53 Compound (3) 43
Compound (4) 58 Compound (5) 40 Compound (12) 53 Compound (13) 54
Compound (14) 55 Compound (15) 55 Compound (16) 58
Example 3
[0207] Preparation of a thermochromic pigment composition:
[0208] A thermochromic pigment composition is prepared by mixing
2.2 parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 2.2 parts by weight of
4,4'-(hexafluoroisopropylidene) diphenol (compound (B1), CAS no.:
1478-61-1), 2.2 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.
79-97-0), and 93.4 parts by weight of the compound (4) that was
synthesized previously (compound (C)). The mixture obtained is
heated under stirring at a temperature of 110.degree. C. for 45
minutes until compounds (A), (B1), and (B2) have been completely
solubilized in compound (C).
[0209] Preparation of thermochromic pigment microcapsules:
[0210] 7.5 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 33% by weight
of copolymer) are neutralized with 9.2 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4. This
solution is diluted with 41.0 parts by weight of water, and the
mixture is emulsified with a homogenizer at a speed of at least 15
ms.sup.-1. 25.6 parts by weight of the thermochromic pigment
composition that was prepared previously are added, and the
emulsion obtained is maintained at a temperature of 85.degree. C.
for 30 minutes. 16.7 parts by weight of a melamine-formaldehyde
prepolymer (50% by weight aqueous solution of prepolymer) are then
added to the mixture dropwise. The reaction medium is then heated
to a temperature of 90.degree. C. and mixed at a speed of at least
15 ms.sup.-1 for 4 hours.
[0211] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 4.2 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0212] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 58.degree.
C. with a hysteresis effect of the color.
Example 4
[0213] Preparation of a thermochromic pigment composition:
[0214] A thermochromic pigment composition is prepared by mixing 3
parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 2.5 parts by weight of
4,4'-(hexafluoroisopropylidene) diphenol (compound (B1), CAS no.:
1478-61-1), 2.5 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.
79-97-0), and 92 parts by weight of compound (8) that was
synthesized previously (compound (C)).
[0215] The mixture obtained is heated under stirring at a
temperature of 110.degree. C. for 1 hour until compounds (A), (B1),
and (B2) have been completely solubilized in compound (C).
[0216] Preparation of thermochromic pigment microcapsules:
[0217] 7.5 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 33% by weight
of copolymer) are neutralized with 8.7 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4. This
solution is diluted with 42.6 parts by weight of water, and the
mixture is emulsified with a homogenizer at a speed of at least 15
ms.sup.-1. 25.2 parts by weight of the thermochromic pigment
composition that was prepared previously are added, and the
emulsion obtained is maintained at a temperature of 90.degree. C.
for 30 minutes. 16.0 parts by weight of a melamine-formaldehyde
prepolymer (50% by weight aqueous solution of prepolymer) are then
added to the mixture dropwise. The reaction medium is then heated
to a temperature of 90.degree. C. and mixed at a speed of at least
15 ms.sup.-1 for 4 hours.
[0218] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 4.6 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0219] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 71.degree.
C. with a hysteresis effect of the color.
Example 5
[0220] Preparation of a thermochromic pigment composition:
[0221] A thermochromic pigment composition is prepared by mixing
2.2 parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 2.2 parts by weight of
4,4'-(hexafluoroisopropylidene) diphenol (compound (B1), CAS no.:
1478-61-1), 2.2 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.
79-97-0), and 93.4 parts by weight of the compound (15) that was
synthesized previously (compound (C)).
[0222] The mixture obtained is heated under stirring at a
temperature of 110.degree. C. for 30 minutes until compounds (A),
(B1), and (B2) have been completely solubilized in compound
(C).
[0223] Preparation of a microencapsulated thermochromic
pigment:
[0224] 7.6 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 33% by weight
of copolymer) are neutralized with 9.4 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4. This
solution is diluted with 39.6 parts by weight of water, and the
mixture is emulsified with a homogenizer at a speed of at least 15
ms.sup.-1. 26.7 parts by weight of the thermochromic pigment
composition that was prepared previously are added, and the
emulsion obtained is maintained at a temperature of 80.degree. C.
for 30 minutes. 16.7 parts by weight of a melamine-formaldehyde
prepolymer (50% by weight aqueous solution of prepolymer) are then
added to the mixture dropwise. The reaction medium is then heated
to a temperature of 90.degree. C. and mixed at a speed of at least
15 ms.sup.-1 for 4 hours.
[0225] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 3.7 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0226] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 55.degree.
C. with a hysteresis effect of the color.
[0227] Preparation of an ink composition:
[0228] 10.8 parts by weight of glycerin (cosolvent) are heated to a
temperature of 30.degree. C. under stirring with a paddle. 0.2
parts by weight of benzotriazole (anticorrosive) and 0.2 parts by
weight of an aqueous solution comprising 2.5% by weight of
1,2-benzisothiazolin-3-one and 2.5% by weight of
2-methyl-4-isothiazolin-3-one (biocide), 0.5 parts by weight of an
aqueous dispersion of a polysiloxane copolymer (aqueous dispersion
at 50% by weight of polymer) (antifoam), and 0.5 parts by weight of
a polyether polyol (surfactant) are then added. The mixture is
stirred until the additives have been completely solubilized. 0.5
part by weight of xanthan gum (rheology modifier) is added slowly
for 15 minutes. After dispersion of the rheology modifier, 26.8
parts by weight of distilled water are added. The ink composition
obtained is stirred for 3 hours, whereupon 60 parts by weight of an
aqueous dispersion of thermochromic pigment microcapsules that was
prepared above (aqueous dispersion 30% by weight of thermochromic
pigment microcapsules) are added. The pH of the ink composition is
adjusted to pH=8 with 0.5 parts by weight of triethanolamine. The
blue ink is then dispersed with a disperser at a speed of at least
15 ms.sup.-1 for 30 minutes. The ink composition is degassed under
reduced pressure prior to injection into ink cartridges.
Example 6
[0229] Preparation of a thermochromic pigment composition:
[0230] A thermochromic pigment composition is prepared by mixing
2.3 parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 1.9 parts by weight of
4,4'-(hexafluoroisopropylidene) diphenol (compound (B1), CAS no.:
1478-61-1), 1.9 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.:
79-97-0), and 93.9 parts by weight of compound (2) that was
synthesized previously (compound (C)). The mixture obtained is
heated under stirring at a temperature of 110.degree. C. for 45
minutes until compounds (A), (B1), and (B2) have been completely
solubilized in compound (C).
[0231] Preparation of thermochromic pigment microcapsules:
[0232] 9.3 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 27% by weight
of copolymer) are neutralized with 16.3 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4.5.
This solution is diluted with 27.6 parts by weight of water, and
the mixture is emulsified with a homogenizer at a rate of at least
15 ms.sup.-1. 27.0 parts by weight of the previously prepared
thermochromic pigment composition are added, and the emulsion
obtained is maintained at a temperature of 85.degree. C. for 30
minutes. 19.8 parts by weight of a melamine-formaldehyde prepolymer
(50% by weight aqueous solution of prepolymer) are then added to
the mixture dropwise. The reaction medium is then heated to a
temperature of 90.degree. C. and mixed at a speed of at least 15
ms.sup.-1 for 4 hours.
[0233] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 2.8 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0234] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 54.degree.
C. with a hysteresis effect of the color.
[0235] Preparation of an ink composition:
[0236] 10.5 parts by weight of glycerin (cosolvent) are heated to a
temperature of 30.degree. C. under stirring with a paddle. 0.2
parts by weight of benzotriazole (anticorrosive) and 0.2 parts by
weight of an aqueous solution comprising 2.5% by weight of
1,2-benzisothiazolin-3-one and 2.5% by weight of
2-methyl-4-isothiazolin-3-one (biocide), 0.5 parts by weight of an
aqueous dispersion of a polysiloxane copolymer (aqueous dispersion
at 50% by weight of polymer) (antifoam), and 0.8 parts by weight of
a diester sulfosuccinate (surfactant) are then added. The mixture
is stirred until the additives have been completely solubilized.
0.5 parts by weight of xanthan gum (rheology modifier) is added
slowly for 15 minutes. After dispersion of the rheology modifier,
26.8 parts by weight of distilled water are added. The ink
composition obtained is stirred for 3 hours, whereupon 60 parts by
weight of an aqueous dispersion of thermochromic pigment
microcapsules that was prepared above (aqueous dispersion 30% by
weight of thermochromic pigment microcapsules) are added. The pH of
the ink composition is adjusted to pH=8 with 0.5 parts by weight of
triethanolamine. The blue ink is then dispersed with a disperser at
a speed of at least 15 ms.sup.-1 for 30 minutes. The ink
composition is degassed under reduced pressure prior to injection
into cartridges.
Example 7
[0237] Preparation of a thermochromic pigment composition:
[0238] A thermochromic pigment composition is prepared by mixing
2.2 parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 2.0 parts by weight of
4,4'-(hexafluoroisopropylidene)diphenol (compound (B1), CAS no.:
1478-61-1), 2.0 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.
79-97-0), and 93.8 parts by weight of compound (9) that was
synthesized previously (compound (C)). The mixture obtained is
heated under stirring at a temperature of 110.degree. C. for 45
minutes until compounds (A), (B1), and (B2) have been completely
solubilized in compound (C).
[0239] Preparation of thermochromic pigment microcapsules:
[0240] 9.0 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 27% by weight
of copolymer) are neutralized with 15.7 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4.5.
This solution is diluted with 28.1 parts by weight of water, and
the mixture is emulsified with a homogenizer at a rate of at least
15 ms.sup.-1. 28.1 parts by weight of the previously prepared
thermochromic pigment composition are added, and the emulsion
obtained is maintained at a temperature of 85.degree. C. for 30
minutes. 19.1 parts by weight of a melamine-formaldehyde prepolymer
(50% by weight aqueous solution of prepolymer) are then added to
the mixture dropwise. The reaction medium is then heated to a
temperature of 90.degree. C. and mixed at a speed of at least 15
ms.sup.-1 for 4 hours.
[0241] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 4.2 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0242] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 56.degree.
C. with a hysteresis effect of the color.
Example 8
[0243] Preparation of a thermochromic pigment composition:
[0244] A thermochromic pigment composition is prepared by mixing
2.2 parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 2.0 parts by weight of
4,4'-(hexafluoroisopropylidene)diphenol (compound (B1), CAS no.:
1478-61-1), 2.0 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.
79-97-0), and 93.8 parts by weight of compound (14) that was
synthesized previously (compound (C)). The mixture obtained is
heated under stirring at a temperature of 110.degree. C. for 45
minutes until compounds (A), (B1), and (B2) have been completely
solubilized in compound (C).
[0245] Preparation of thermochromic pigment microcapsules:
[0246] 9.4 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 27% by weight
of copolymer) are neutralized with 16.2 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4.5.
This solution is diluted with 27.5 parts by weight of water, and
the mixture is emulsified with a homogenizer at a rate of at least
15 ms.sup.-1. 27.3 parts by weight of the previously prepared
thermochromic pigment composition are added, and the emulsion
obtained is maintained at a temperature of 85.degree. C. for 30
minutes. 19.6 parts by weight of a melamine-formaldehyde prepolymer
(50% by weight aqueous solution of prepolymer) are then added to
the mixture dropwise. The reaction medium is then heated to a
temperature of 90.degree. C. and mixed at a speed of at least 15
ms.sup.-1 for 4 hours.
[0247] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 3.2 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0248] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 55.degree.
C. with a hysteresis effect of the color.
[0249] Preparation of an ink composition:
[0250] 10.3 parts by weight of glycerine (cosolvent) are heated to
a temperature of 30.degree. C. under stirring with a paddle. 0.2
parts by weight of benzotriazole (anticorrosive) and 0.2 parts by
weight of an aqueous solution comprising 2.5% by weight of
1,2-benzisothiazolin-3-one and 2.5% by weight of
2-methyl-4-isothiazolin-3-one (biocide), 0.5 parts by weight of an
aqueous dispersion of a polysiloxane copolymer (aqueous dispersion
at 50% by weight of polymer) (antifoam), and 0.5 parts by weight of
a polyether polyol (surfactant) are then added. The mixture is
stirred until the additives have been completely solubilized. 0.5
part by weight of xanthan gum (rheology modifier) is added slowly
for 15 minutes. After dispersion of the rheology modifier, 26.8
parts by weight of distilled water are added. The ink composition
obtained is stirred for 3 hours, whereupon 60 parts by weight of an
aqueous dispersion of thermochromic pigment microcapsules that was
prepared above (aqueous dispersion 30% by weight of thermochromic
pigment microcapsules) are added. The pH of the ink composition is
adjusted to pH=8 with 1 part by weight of NaOH. The blue ink is
then dispersed with a disperser at a speed of at least 15 ms.sup.-1
for 30 minutes. The ink composition is degassed under reduced
pressure prior to injection into ink cartridges.
Example 9
[0251] Preparation of a thermochromic pigment composition:
[0252] A thermochromic pigment composition is prepared by mixing
2.2 parts by weight of
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azapht-
halide (compound (A), CAS no.: 69898-40-4), 2.0 parts by weight of
4,4'-(hexafluoroisopropylidene)diphenol (compound (B1), CAS no.:
1478-61-1), 2.0 parts by weight of
2,2-bis(4-hydroxy-3-methylphenyl)propane (compound (B2), CAS no.
79-97-0), and 93.8 parts by weight of compound (16) that was
synthesized previously (compound (C)). The mixture obtained is
heated under stirring at a temperature of 110.degree. C. for 45
minutes until compounds (A), (B1), and (B2) have been completely
solubilized in compound (C).
[0253] Preparation of thermochromic pigment microcapsules:
[0254] 9.3 parts by weight of an aqueous solution of a copolymer of
maleic anhydride and methyl vinyl ether (solution at 27% by weight
of copolymer) are neutralized with 16.0 parts by weight of an
aqueous solution of sodium hydroxide (1.0 M solution) at pH=4.5.
This solution is diluted with 27.7 parts by weight of water, and
the mixture is emulsified with a homogenizer at a rate of at least
15 ms.sup.-1. 27.1 parts by weight of the previously prepared
thermochromic pigment composition are added, and the emulsion
obtained is maintained at a temperature of 85.degree. C. for 30
minutes. 19.9 parts by weight of a melamine-formaldehyde prepolymer
(50% by weight aqueous solution of prepolymer) are then added to
the mixture dropwise. The reaction medium is then heated to a
temperature of 90.degree. C. and mixed at a speed of at least 15
ms.sup.-1 for 4 hours.
[0255] A slurry consisting of microcapsules of thermochromic
pigment dispersed in an aqueous solvent is obtained, the
microcapsules having a diameter of 3.1 .mu.m d90 as determined
using a Zetasizer Nano ZS system from Malvern Instruments with
illumination at 632 nm.
[0256] The thermochromic pigment microcapsules obtained have the
property of changing color from blue to colorless above 58.degree.
C. with a hysteresis effect of the color.
[0257] Determination of the discoloration and recoloration
temperatures of the thermochromic pigment microcapsules prepared in
examples 3, 4, 5, 6, 7, 8, and 9:
[0258] The transition temperatures of thermochromic pigment
microcapsules obtained were measured by means of differential
scanning calorimetry (DSC) using a TA Instruments Q20 apparatus
over a temperature range of -50 to 100.degree. C. at
heating/cooling rates of +/-20.degree. C./minute. The temperatures
measured are shown in table 3 below.
TABLE-US-00003 TABLE 3 Transition temperatures of the thermochromic
pigment microcapsules prepared in examples 3, 4, 5, 6, 7, 8, and 9
Color change colored T1 T2 T3 T4 T.sub.H T.sub.G colorless
(.degree. C.) (.degree. C.) (.degree. C.) (.degree. C.) (.degree.
C.) (.degree. C.) .DELTA.H Thermochromic blue colorless -20 -10 48
58 -15 53 68 pigment microcapsules comprising compound (4) (example
3) Thermochromic blue colorless 0 10 55 71 5 63 58 pigment
microcapsules comprising compound (8) (example 4) Thermochromic
blue colorless -5 5 40 55 0 48 48 pigment microcapsules comprising
compound (15) (example 5) Thermochromic blue colorless -8 -5 40 54
-7 47 54 pigment microcapsules comprising compound (2) (example 6)
Thermochromic blue colorless -7 18 38 56 6 47 41 pigment
microcapsules comprising compound (9) (example 7) Thermochromic
blue colorless 5 10 35 55 8 45 37 pigment microcapsules comprising
compound (14) (example 8) Thermochromic blue colorless 8 12 36 58
10 47 37 pigment microcapsules comprising compound (16) (example 9)
The transition temperatures measured are as follows: T1:
temperature of complete recoloration, T2: temperature of partial
recoloration, T3: temperature of partial discoloration, T4:
temperature of complete discoloration, T H = T 1 + T 2 2 ,
##EQU00001## T G = T 3 + T 4 2 , ##EQU00002## .DELTA.H = hysteresis
range = T.sub.G - T.sub.H.
* * * * *